Mountain biking, a branch of the bicycle industry that has become increasingly popular, has evolved to provide off-road equipment for transportation, racing, and recreation. The derailleur assembly of a bike often disables when an object, such as a stick or rock, impacts the derailleur or becomes wedged between the derailleur and the frame or the wheel of the bicycle. Damage to the frame, the derailleur, or the derailleur hanger almost always results. With the limitations on weight and space, it is impractical for a rider to carry sufficient spare parts or tools to repair the damage at the site. The repairs, if possible, will be costly and time consuming. As a result, the bike becomes disabled, and the rider is stranded.
In the past, a weak link between the derailleur and the frame has been used to attempt to protect the bicycle frame from damage. A deformable derailleur hanger protects the frame but does not extend to preserving the derailleur. A softer mounting bolt has a tendency to fail and flex excessively under reasonable loading. In addition, neither of these designs makes field repair practicable.
For the foregoing reasons, there is a need for a device that is small, inexpensive, and serviceable by the rider which reduces repair time and damage to the frame, the derailleur, and the derailleur hanger.